Strip bending and forming machine



July 29, 1941. BQRTQN 2,251,218

' STRIP BENDING "AND FORMINGMACHINE Filed Nov. 3, 1939 I 2 Sheets-Sheet l INVENTOR Ala/yr? E. Barton T RNEY July 29, 1941. A. E. BORTON STRIP BENDING AND FORMING MACHINE Filed Nov. 3, 1939 2 Sheets-Sheet 2 INVENTOR Alwyn E. Barton wxm A ORNEY Patented July 29, 1941 STRI? BENDING AND FORMING MACHINE Alwyn E. Borton, South Orange, N; 3., assignor to Associated Patentees, Inc Ampere, N. .L, a

corporation of New Jersey Application November 3, 1939; Serial N 302,638

10 'Claims.

This'invention relates to the bending and forming-of strip stock.

In performing some bending operations, particularly Where the strip material has to be more or less doubled upon itself, it is clifficult if not impossible, or at least impractical to work in a mechanical bending tool in the time permitted between operations of other, co-related tools.

It is one of the objects of this invention to solve this difiiculty and to accomplish the necessary bending of the stock in the time permitted between operations of other related tools and Without interfering with or slowing up the action of such other tools.

Further objects are to provide mechanism for the purposes mentioned, which will be of relatively simple nature, practical and efiicient and adaptable to machines now in use.

The foregoing and other desirable objects are attained by the novel features of construction, combinations and relations of parts all as hereinafter described, illustrated in the accompanying drawings and covered broadly in the claims.

The drawings referred to show a practical commercial embodiment of the invention, but as this is intended primarily by way of disclosure, it will be understood that modifications and changes, as regards this illustration may be made all within the true intent and broad scope of the invention.

Fig 1 in the drawings is a broken plan View, with parts in section, of a multiple slide machine of the character disclosed in the Borton Patents 1,883,513 and 1,919,999, with features of the present invention incorporated therein.

Fig. 2 is a broken sectional view as on substantially the plane of line 22 of Fig. 1.

Figs. 3, 4, 5 and 6 are broken part sectional details illustrating successive stages in the bending and shaping of the stock.

Fig. '7 is a broken part sectional detail illustrating the stripping of the formed pieces off the mandrel.

Fig. 8 is a broken perspective view illustrating the bending of the stock about the mandrel.

In Figs, 1 and 2, the bed of a multiple slide machine, such as illustrated in the Borton Patents 1,883,513 and 1,919,999 is indicated at It], with the front and back shafts H and i2, carrying cams l3, I4, opera-ting through cam rolls l5, US, the cooperating tool slides i1, it.

The strip stock is indicated at 9, advanced by theusual feed slide mechanism 45; of these machines through a'guide- 29, into position between the cooperatingbending tools 2|; 22, on slides l1, I8.

A knife 23, associated with the guide-20, cuts the strip to proper'lengths, this knife being carried'by slide 24-, having a roll 25: engagingcam 26; on the front cam shaft I I.

Positioned between the bending tools is a mandrel or forming post, consisting in thepresent disclosure of a-main post or mandrelZ'l, and spaced 'wires-28at opposite sides of the same.

The bending tools are shaped to fit the stock closely about the compound mandrel; made up of the center post 21, and side wires 28'; and they are timed so that-upon severance of'th'e proper length of stock at l9; Fig. 3, the tools willcome together to bend the firsthalf I911 of" this stock about the lower sides of the'forming post andwires as in Fig; 4, and will throw the secondh'alf lBb' of' the stock upw'ard'in an arc about'the'left handforming-wire 28; Before this second'half can be formed, the upper-bending tool 22,;must be retracted and 'thestock doubled over'infront' of the same.

In the present invention, after thebending'of the first half of the stock, the upper bending tool retreats, the bent portion: is held by the lower bending tool and the remainder of the strip is-then quickly doubled over in-front of the retracted tool by a sudden blast of compressed air or the like, accurately directed at the outstanding portion of the stock.

The condition and action last referred to isindicated'in Fig. 5, where the first portion I9a of the, formed stock is. shown held byv the lower tool 2|, against the forming post and wires 21,. 28, and the second portion I91), of the stock is shown first in broken lines in the outstanding relation it occupies as the upper bending tool 22 retreats and then in full lines in the position to which it is bent by the blast of compressed air or the like, delivered by the nozzle 29. This jet of air is of sufiicient force and extent to practically complete the bending of the outstanding portion of the stock about the left hand forming wire and to lay this part of the stock over against the intermediate post 21, in position to be finally formed by the upper tool 22, Fig. 6, about the upper sides of the post and wires.

As appears more particularly in Figs. 1, 2 and 8, the air nozzle is mounted on an endwise acting slide 30, actuated from the lefthand end cam shaft (not shown) of the machine. This slide is timed in the present disclosure as indicated in Figs. 4 and 5, to advance the nozzle intoposition close in back of the unbent' strip" as the upper slide 22 recedes and to then retreat as the upper slide comes down for the second bending operation, as in Fig. 5.

The structure of the nozzle may vary, but in the present disclosure, it comprises a block 3|, suitably secured on the slide as by bolt 3'2, and having an air passage 33, through the outer end of the same opening to an angularly recessed portion 3 i, cut in the side of the block and into which is fitted and secured the jet piece 35. having a fiat groove 38, in the face toward the end of passage 33. This flat groove has its width disposed transversely of the strip stock to apply pressure of the blast substantially across the full width of the stock.

The jet block 35, is shown as elongated beyond the mouth of the slot 35, and provided with an inclined reaction surface 3?, which in the advanced position of the nozzle, Fig. 5, extends close to the bending point of the strip. This reaction surface extending from the end of the orifice and along a generally parallel line with the jet serves as an abutment wall for the side of the jet furthest from the stock. This has the effect of stiffening and steadying the jet and preventing loss of energy by dispersion. The taper of the reaction extension 31, of the jet block enables approach of the same close to the bending point of the strip and if desired, actual contact with the strip to initiate or aid the bending movement, 7

Fig. 5.

The compressed air or other fluid is supplied to the nozzle in the present instance, by flexible tubing 38, connected with an air compressor or other source of fluid pressure. These fluid pressure connections include, in this illustration, a valve 39, having a stern Gil, Fig. 2, operable by a rocker All, carrying a roll 12, Fig. 1, riding a cam 13, on the back cam shaft I2. This cam is timed to open the valve at the proper moment to release the stock-bending blast the moment the stock is ready to bend across the face of the receding tool 22. This blast need be but momentary and the valve therefore may be snapped closed the instant the air blast has accomplished the stock bending action. Because of the practically instantaneous effect of the blast, the second bending tool 22 need not hesitate at the end of its outward stroke and may be closed immediately upon the portion or stock which has been air bent across the face of the same. The action of the bending tools thus is not restricted or delayed by time necessary for a tool to intervene between the two. Also for some operations, where it would be impossible to use an intermediate tool, the air blast may be employed to effect bending of the material which otherwise could not be accomplished.

In Fig. '7, a stripper is indicated at i l, carried by a plunger 45, for sliding the formed blanks down off the forming post and wires, this construction and arrangement being similar to that covered in the Borton Patent 1,919,999, wherein a previously formed blank holds the wires in proper relation to the forming post, while the second blank is being formed thereon and the action of the stripper is to force off only the end blank, leaving the last formed blank in position for the next bending operation.

The stock bending nozzle may be used on various kinds of strip stock, the size and shape of the jet and pressure employed being suited to the size, flexibility and other characteristics of the strip material. Perforate or porous material may be bent by the jet, as well as imperforate strip stock.

In the construction herein disclosed, the tip of the jet nozzle is shaped to fit that part of the post about which the stock is bent, substantially as indicated at 4?, and the jet slide is advanced on the completion of the air jet bending movement to actually engage the stock as in Figs. 5 and 8, to set the material so that it will stay in the bent position shown and will not spring back from in front of the then advancing tool slide.

What is claimed is:

1. Apparatus of the character disclosed comprising in combination with a forming post, a tool for bending and holding strip material about one side of said forming post with a free portion of said strip projecting at an angle away from the forming post, a blast nozzle providing a fluid jet directed at said free projecting portion of the strip for blowing said projecting portion of the held strip material about the opposite side of the forming post and a second tool operable toward said opposite side of the forming post for shaping said projecting bent portion of the strip material about said opposite side of the forming post and means for advancing said second bending tool after said blast nozzle has blown the projecting portion of the held strip material into position in front of said second tool.

2. In combination with a forming post and tools operable toward and away from opposite sides of said forming post, a nozzle positioned to direct a blast against strip material held by one of said tools against one side of said forming post and means for advancing said nozzle toward said forming post upon movement of one of said tools away from said forming post, said strip material being held by one of said tools with a portion of the strip material projecting [ree away from the forming post and said nozzle being positioned to direct the blast against said free projecting portion of the strip material and in a direction to bend the strip about the opposite 9 side of the post from the tool which holds the strip material to the post.

3. In combination, opposed strip bending slides, an intermediate forming member between the same and a jet nozzle intermediate the slides and providing a blast of fluid directed at an angle to the movement of one of said strip bending slides for blowing a projecting portion of strip material held by said slide against one side of the intermediate forming member about the opposite side of said forming member into position for engagement by the other bending slide and actuating mechanism timed to retract the second bending slide and to effect operation of the strip bending jet when said slide is retracted.

4. In combination with means for operating on strip material, a jet nozzle for bending said strip material and having an orifice elongated transversely oi the strip material and having further a reaction surface on the nozzle at the back of said orifice and extending toward the strip to be bent and terminating in a portion conformed to engage and mechanically bend the strip material previously bent by the combined action of the jet and reaction surface and means for moving said nozzle into engagement with the strip material.

5. In combination, opposed bending slides, a former therebetween, a slide operating at an angle to said bending slides and a strip bending jet nozzle carried by said last mentioned slide,

former and said strip bending jet being directed by said nozzle toward said projecting free portion of the strip.

6. In combination, opposed bending slides, a former therebetween, a slide operating at an angle .to said bending slides, a strip bending jet nozzle carried by said last mentioned slide, flexible supply connections to said jet nozzle and valve mechanism timed to intermittently admit pressure fluid through said flexible connections, means for operating said opposed bending slides and means for advancing said nozzle carrying slide in time with a retractive movement with one of said bending slides and at a time when the strip is held by the other bending slide with TI. portion of the same projecting away from the former and said strip bending jet being directed by said nozzle toward said projecting free portion of the strip.

'7. In combination, means for holding strip material with a portion free for bending movement, a jet bending nozzle providing a strip bending fluid blast toward and having a movement toward and into actual engagement with said free portion of the held strip material, said holding means including a former and reciprocating bending dies at opposite sides of said former and said jet bending nozzle being movable into cooperative relation with said former at an angle to the movement of said bending dies and at a time when one of said bending dies is retracted from said former.

8. In a machine of the character disclosed, the combination of a former and a forming tool cooperating therewith to confine strip stock against one face of said former with a free portion of the strip stock projecting at an angle away from the former, a nozzle having a jet opening directed at said free projecting portion of said strip material, means for projecting a fluid blast from said jet opening at said projecting portion of strip material at a time when said material is held by said forming tool to bend the strip material by said blast over toward the opposite face of said former and a second forming tool cooperable with said opposite face of the former and means for actuating same at a time when the free projecting portion of the strip material is blown by the nozzle toward said opposite face of the former.

9. In a machine of the character disclosed, the combination of a former and a forming tool cooperating therewith to confine strip stock against one face of said former with a free portion of the strip stock projecting at an angle away from the former, a nozzle having a jet opening directed at said free projecting portion of said strip material, means for projecting a fluid blast from said jet opening at said projecting portion of strip material at a time when said material is held by said forming tool to bend the strip material by said blast over toward the opposite face of said former, a second forming tool cooperable with said opposite face of the former, means for actuating same at a time when the free projecting portion of the strip material is blown by the nozzle toward said opposite face of the former and a reaction surface disposed in opposition to the projecting portion of the strip material, to thereby confine the strip bending blast against said projecting strip material.

10. In a machine of the character disclosed, the combination of a former and a forming tool cooperating therewith to confine strip stock against one face of said former with a free portion of the strip stock projecting at an angle away from the former, a nozzle having a jet opening directed at said free projecting portion of said strip material, means for projecting a fluid blast from said jet opening at said projecting portion of strip material at a time when said material is held by said forming tool to bend the strip material by said blast over toward the opposite face of said former, a second forming tool cooperable with said opposite face of the former, means for actuating same at a time when the free projecting portion of the strip material is blown by the nozzle toward said opposite face of the former, said blast bending nozzle having a portion mechanically cooperable with the former and means for shifting said nozzle to eifect strip bending cooperation of the blast with the projecting part of the strip and mechanical strip forming c0- operation of the nozzle with the former.

ALWYN E. BORTON. 

